Contents

A reporter named Kathy Lane comes to Theodor Geisel's home in order to do a report on the famous Dr. Seuss, where she meets a strange character. When Kathy asks to use him as a source, he reveals himself to be The Cat in the Hat. Curiosity allows her to open a magical book labeled "Open a book, open up your imagination", which pulls her into the world of Dr. Seuss. The Cat in the Hat shows Kathy a door which leads to a beach. On the beach, they read The Sneetches and Other Stories. Kathy then falls into a kitchen where she meets Mr. Hunch from Hunches in Bunches. They eat lunch and read McElligot's Pool.

Kathy then ends up in a jungle where she notices Horton the Elephant. She then reads Horton Hatches the Egg. The Cat in the Hat appears again. Soon, Kathy wanders into a room which is explained to be "The World of Advertising". The Ad Man and the Ad Woman explain to Kathy about Dr. Seuss in the advertising business. The room soon rocks and Kathy is transported to Mulberry Street where she meets Marco. She helps Marco come up with a story to tell his father when he gets home from walking from school.

The story changes as Kathy and Marco add exciting things to it. The story starts out as a horse pulling a cart. But it soon turns into a tale with an elephant, the mayor, planes with confetti, a Rajah, a band playing music and other things completely random. Soon, Marco keeps the story as a horse pulling a cart. He then leaves.

Sgt. Mulvaney then appears and brings Kathy to a revolving door that is shown to represent the way people rejected Dr. Seuss' first book for publishing. The Sergeant then goes through the door and disappears.

Kathy goes through the door and ends up in a hall with the Cat in the Hat. The Cat explains to Kathy about some of Dr. Seuss' dark political cartoons. An alarm goes off and he disappears.

Kathy soon walks into a room and meets The Voice of America. The Voice of America then shows Kathy the documentary Hitler Lives, which was made by Theodor Geisel and his wife.

Next, Kathy shows up at the street of the lifted Lorax where she put in a payment (15 cents, a nail, and the shell of a great, great, great grandfather snail) written on paper in a bucket after which The Once-ler hoisted up the bucket with all those things, collected them, brought down a speaker and told the story of The Lorax.

After planting a new Truffula Tree, marching music sounded, indicating a butter battle which represents The Butter Battle Book.

The finale segment of the film sees Kathy and the Cat in the Hat visit the library where they sing Oh, the Places You'll Go!, later they were transported back to Dr. Seuss' house where Kathy's adventure ended.

The film features many of Dr. Seuss's stories, though they are edits of older adaptations, while some of the adaptations are newly created live-action versions. It also includes some of his political work, including excerpts of his short subject Hitler Lives.